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Lessons In Electric Circuits -- Volume V

Chapter 3

CONDUCTOR AND INSULATOR TABLES

Copper wire gage table

Soild copper wire table: below

Soild copper wire table:

SizeDiameterCross-sectionalareaWeight
AWGinchescir. milssq. incheslb/1000 ft
4/00.4600211,6000.1662640.5
3/00.4096167,8000.1318507.9
2/00.3648133,1000.1045402.8
1/00.3249105,5000.08289319.5
10.289383,6900.06573253.5
20.257666,3700.05213200.9
30.229452,6300.04134159.3
40.204341,7400.03278126.4
50.181933,1000.02600100.2
60.162026,2500.0206279.46
70.144320,8200.0163563.02
80.128516,5100.0129749.97
90.114413,0900.0102839.63
100.101910,3800.00815531.43
110.090748,2340.00646724.92
120.080816,5300.00512919.77
130.071965,1780.00406715.68
140.064084,1070.00322512.43
150.057073,2570.0025589.858
160.050822,5830.0020287.818
170.045262,0480.0016096.200
180.040301,6240.0012764.917
190.035891,2880.0010123.899
200.031961,0220.00080233.092
210.02846810.10.00063632.452
220.02535642.50.00050461.945
230.02257509.50.00040011.542
240.02010404.00.00031731.233
250.01790320.40.00025170.9699
260.01594254.10.00019960.7692
270.01420201.50.00015830.6100
280.01264159.80.00012550.4837
290.01126126.70.000099540.3836
300.01003100.50.000078940.3042
310.00892879.700.000062600.2413
320.00795063.210.000049640.1913
330.00708050.130.000039370.1517
340.00630539.750.000031220.1203
350.00561531.520.000024760.09542
360.00500025.000.000019630.07567
370.00445319.830.000015570.06001
380.00396515.720.000012350.04759
390.00353112.470.0000097930.03774
400.0031459.8880.0000077660.02993
410.0028007.8420.0000061590.02374
420.0024946.2190.0000048840.01882
430.0022214.9320.0000038730.01493
440.0019783.9110.0000030720.01184

Copper wire ampacity table

Ampacities of copper wire: below

Ampacities of copper wire, in free air at 30o C:

INSULATION TYPE:
RUW, TTHW, THWNFEP, FEPB
TWRUHTHHN, XHHW
SizeCurrent RatingCurrent RatingCurrent Rating
AWG@ 60 degrees C @ 75 degrees C @ 90 degrees C
20*9*12.5
18*1318
16*1824
14253035
12303540
10405055
8607080
68095105
4105125140
2140170190
1165195220
1/0195230260
2/0225265300
3/0260310350
4/0300360405

* = estimated values; normally, these small wire sizes are not manufactured with these insulation types, above.

Coefficients of specific resistance

Specific resistance table: below

Specific resistance at 20o C:

MaterialElement/Alloy(ohm-cmil/ft)(ohm-cm·10-6)
NichromeAlloy675112.2
Nichrome VAlloy650108.1
ManganinAlloy29048.21
ConstantanAlloy272.9745.38
Steel*Alloy10016.62
PlatinumElement63.1610.5
IronElement57.819.61
NickelElement41.696.93
ZincElement35.495.90
MolybdenumElement32.125.34
TungstenElement31.765.28
AluminumElement15.942.650
GoldElement13.322.214
CopperElement10.091.678
SilverElement9.5461.587
    *       =    Steel   alloy   at   99.5%    iron,   0.5%    carbon     

Temperature coefficients of resistance

Temperature coefficient table: below

Temperature coefficient (α) per degree C:

MaterialElement/AlloyTemp. coefficient
NickelElement0.005866
IronElement0.005671
MolybdenumElement0.004579
TungstenElement0.004403
AluminumElement0.004308
CopperElement0.004041
SilverElement0.003819
PlatinumElement0.003729
GoldElement0.003715
ZincElement0.003847
Steel*Alloy0.003
NichromeAlloy0.00017
Nichrome VAlloy0.00013
ManganinAlloy0.000015
ConstantanAlloy±0.000074
*   =  S teel alloy at 99.5%    iron, 0.5%    carbon 

Critical temperatures for superconductors

Critical temperature, superconductors below

Critical temperatures given in Kelvins

MaterialElement or AlloyCritical temperature(K)
AluminumElement1.20
CadmiumElement0.56
LeadElement7.2
MercuryElement4.16
NiobiumElement8.70
ThoriumElement1.37
TinElement3.72
TitaniumElement0.39
UraniumELement1.0
ZincElement0.91
Niobium/TinAlloy18.1
Cupric sulphideCompound1.6

Critical temperatures, high temperature superconuctors below

Critical temperatures, high temperature superconuctors in Kelvins

MaterialCritical temperature(K)
HgBa2Ca2Cu3O8+d150 (23.5 GPa pressure)
HgBa2Ca2Cu3O8+d133
Tl2Ba2Ca2Cu3O10125
YBa2Cu3O790
La1.85Sr0.15CuO440
Cs3C6040(15 Kbar pressure)
Ba0.6K0.4BiO330
Nd1.85Ce0.15CuO422
K3C6019
PbMo6S812.6

Note: all critical temperatures given at zero magnetic field strength, above.

Dielectric strengths for insulators

Dielectric strength: below

Dielectric strength in kilovolts per inch (kV/in):

Material*Dielectric strength
Vacuum20
Air20 to 75
Porcelain40 to 200
Paraffin Wax200 to 300
Transformer Oil400
Bakelite300 to 550
Rubber450 to 700
Shellac900
Paper1250
Teflon1500
Glass2000 to 3000
Mica5000

* = Materials listed are specially prepared for electrical use, above.

Data

Tables of specific resistance and temperature coefficient of resistance for elemental materials (not alloys) were derived from figures found in the 78th edition of the CRC Handbook of Chemistry and Physics. Superconductivity data from Collier's Encyclopedia (volume 21, 1968, page 640).




Lessons In Electric Circuits copyright (C) 2000-2020 Tony R. Kuphaldt, under the terms and conditions of the Design Science License.

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